Hot gas engine enclosing two thermodynamic cycles



Nov. 3, 1953 c. o. JONKERS ETAL 2,657,528

HOT GAS ENGINE ENCLOSING TWO THERMODYNAMIC CYCLES Filed Nov. 29, 1949 2 Sheets-Sheet l i 5'1 INVNTOR3 Cornefius Otto Jon kers JacbbWllem Laurens K'dhhr,

w R w'ia ml mm A") TLiebe V AGENT Nov. 3, 1953 c. o. JQNKERS ETAL HOT GAS ENGINE. ENCLOSING TWO 'THERMODYNAMIC CYCLES 2 Sheets-Sheet 2 Filed NOV. 29, 1949 JNVENTORS Cornelius Otto Jon kevs,Jacob\Ji\\m LAwmsK'Mkv,

Hcvnmmia MA Q Mbej Liebe,

" Aczm' therewith are opposite. I quently, that one space is a hot space and the other a cold space. In threeand multicycle en- Patented Nov. 3, 1953 HOT GAS ENGINE ENCLOSING TWO THERMODYNAMIC CYCLES Cornelius Otto Jonkers, Jacob Willem Laurens Kiihler, Herre Rinia, and August Albert Liebe, Eindhoven, Netherlands, assignors to Hartford National Bank and Trust Company, Hartford,

Conn., as trustee Application November 29, 1949, Serial No. 130,056 Claims priority, application Netherlands December 24, 1948 11 Claims.

1 This invention relates to hot-gas engines in which at least two closed thermodynamic cycles are performed, the volumes of these cycles being varied by members moving with a suitable phase difference and at least two members acting upon two cycles, similar working spaces being provided on either'side of the movable members. The term hot-gas engine is to be understood to include a refrigerator or a heat pump operating according to the reversed hot-gas engine principle.

In known hot-gas engines comprising reciprocating members, one cycle is, as a rule, acted upon solely by two members moving with a phase difference. The engine has in this case the advantage that no valves or slides are used, such as required, for example, in internal combustion engines and reciprocating steam engines. However, in hot-gas engines having one cycle, owing to the presence of the two movable members, ab-

sorption of energy due to friction during each cycle is comparatively high. A solution was found only with threeand multicycle engines in which the number of moving members was equal to the number of cycles. In order to provide an engine which is advantageous in structural respect, the working spaces above and below the pistons have hitherto been made different. The

term'different applied to working spaces is to I be understood to mean working spaces, in the associated heat exchangers of which the mean directions of flow of heat between the working medium and the medium having thermal contact This means, consegines the space above the movable member in one cylinder has hitherto been connected with the 'space below the movable member in another cylinder, whereas the space below the movable mem- "ber in the first-mentioned cylinder is connected with the space above the movable member in a third cylinder. Thus, for example, hot spaces are provided above all movable members and cold spaces below the movable members, or conversely.

' Ina three-cycle engine, the two remaining spaces in the first and the third cylinder are likewise connected with each other.

Consequently, the number of cycles in such engines is equal to the number of moving members, so that the 'efliciency is comparatively high.

These engines, however, have the disadvantage that medium is liable to leak from the hot space to thecold space and conversely. This leakage of medium and the heat transmission through the 2 wall of the cylinder and through the piston body between the two spaces produces a thermal leakage, so that the efliciency of the engine is adversely afiected.

It is also known to construct a hot-gas reciprocating engine as a two-cycle engine, in which similar working spaces are provided on either side of the moving members.

The term similar working spaces is to be understood to mean working spaces inthe associated heat exchangers of which the mean directions of flow of heat between the working medium and the medium having thermal contact therewith are the same. This means, consequently, that both spaces are hot or both spaces are cold spaces. However, the temperatures in these heat exchangers need not necessarily be the same.

In these hot-gas reciprocating engines of known type the moving members are provided with cylindrical envelopes, whilst one member, i. e. that having cold spaces on either side, is adapted to move in the envelope of the other moving member. Obturation of the space between the two moving members is eifected on the side of the cold spaces. 7 I

This engine provides the possibility, in twocycle engines, of having the two cycles acted upon by only two moving members.-

However, this engine has a limitation in that the communication ducts between the hot and cold spaces are constituted by slots between a stationary wall and the wall of the envelope of a moving member, so that these boundary walls move relatively to one another.

This may involve a considerable thermal leakage along the heat exchangers, which may be provided in a slot. Since the channel associated with one cycle surrounds the channel associated with the other cycle, and since heat is supplied to and abstracted from the working medium from the outside, this supply of heat to or abstraction of heat from the working medium is not of a high order in the inner channel, so that the efliciency of the engine is furthermore adversely affected.

The object of the invention is to provide an improved hot-gas engine.

According to the invention, a hot-gas engine in which at least two closed thermodynamic cycles are performed, the volumes or these cycles being varied by members moving with a suitable phase difference, at least two members acting upon at least two cycles and similar Working spaces being provided 011 either side of the movable members, is characterized in that the comh i ht oi. beelem t ,withthe' other cycle may -,T.h. cent ampl m terial y-lm eriihenf fi coccurmw t a Di t 11 W FhP b r1 oduceaim.examn erii 1 her or part thereof is periodically deformed. In

members having shouldha've" no piston rings, "sincelubrication of cylinder consists such as""rubber;" which "is secured #between the munication ducts between the variable spaces associated with one cycle are bounded by fixed walls. Thermal leakage either through and along the movable member or along any-heat exchangers to be housed'in the ducts is thus substantially avoided.

A regenerator may be provided between the variable spaces associated with'onecycle-in the communication ducts, bounded by th'e'fixed walls.

A heater, a regenerator and a cooler may be provided between the variable sp'aces of onecycle in the communication duct "bounded byfixed walls. This ensures that'jth eat'e' icliaifrige'between the working medium 'and'the'c'aoiirig and heating mediums is of a high order.

If the members movingwith suitable phase difierence are arranged to be o axial, construction may be realized, which is advantageous in structural respect.

One or more of the elements heater, regenerator and cooler, associated with one cycle may be, co-a x ial at'least lone" or more similar e ments.a Q i nothei cyclejforie or more elements associated with the'bne cycle at least substantially surrounding one 6r more sime i1ar el ments associated with'the other" cycle. N In a number oi sections atfrighth'r'i'glies to the axis of a Working spa e andtaken through one or the elements heater, regnerator and ...co0ler.. so i ted. wit Qll preferably be ing divided over at least half the bothone or the sections .,,oi. the element associated with the one cycle and a sectiorr of a simil arfelementi associated be located on an annu- 1ar.strin-.

. incest hecs mb i f e with a suitable phase difference maybe at a'n'l'angle thpm .At least one movable membenmay' reciprocate withoutfriction. 1 I I Where reference is inade to'a frictionless mov- ;ing m'embcnth' ism va lam f y. ,with0 t .frict pn. a ihep d m i i e n sisiobe ue efih d dfi that ber moves without or'substanconditions. Any frictionstilloccurrihg is, for exwhich -would L M gs operating Any rriction sl'iilljc' ccurat the samejc ions.

ring may be con stituted by egitern'al friction internal ,irict n- ."lihf iastrment nfed i fi is the-reciprocating memthe engine accordingvto the invention, it is of particular importance that thernovable members between, heated spacescan movewithout friction,

since in refrigerators the energyfproduced by the. frictionyof ,p-istonrings mayadve rsely affect ,.the .efficiency of the engine, even to an extent cycle, these sections.

cylinder wall and the movable member, a certain amount of play being left between the movable member and the cylinder wall. Thus, frictional.

losses may be reducedwandv-leakagec losses may be substantiallyavoided.

It is particularly advantageous if, in the aforesaid case, the hot-gas engine according to the -themovable'member made of a flexible invention comprises a movable member constructed in the form of a diaphragm.

which is In a further embodiment of the invention, elastic """materialis 'constructed in the form of bellows.

TLubric'ation of-athe movable members may be dispensed within the said embodiments. The embodiments may be used with particular suceess, if-the temperatures prevailing in the workin'g 'space's Orr-either side of the member are "neither particularly high nor particularly low.

--The obturation of the space between a movable member and the :wall of the cylinder may be -constituted by a. labyrinthine slot.

In order that the invention may bev more' clearly'iin'derstoodand readily carried into effect, it

will now be described more fully with meierence to the accompanying drawings, example, in which Fig. l showsia hot-gas engine comprising pistons 'iilithout piston rings, in which the, heater, the cooler and the regenerator associated, with one cyclesurround the heater, the regenerator and the cooler associated with the 'other cycle iv n y of and Fig. 2 is a cross-sectional'view taken on the line II' -II of Fig. 1;

Fig. 3 is a sectional View, taken on the line III-III-'-III or. Fig.4, of a refrigerator; mpris- .ing two pistons, the ,spaceubetween the pistons and thecylinder wall being .obturated by rubher. The heater, the regenerator and the cooler associated with one cycle are housedj'in the same annular space as the heater, the regenerator and the cooler associated-withthe other cycle.

. Fig.4 is .a sectional ,view taken on theline IV JV of Fig. 3.; and, .finally,

Fig, 5 shows a hot-gas. engine comprisin bellows, the heat'exchangers' and the, regenerator associated with one cycle beinaarranged the space between the bellows.

- Referring now to .Figs. 1, and,2,,..aapiston,,Land a piston 2 are. adapted. to. movewith :a suitable phase difierence the' pistons .co-operatingQwith a crankshaft 3. The. pistons. l.,,and, Z. are not provided .with .piston. .,rings. and: reciprocate in the cylinders .with a smallamount ofipla'yivzone cycle is performed in working .spaces,,4,,and 5 and the otherinworking spaces ifi and 1.;..',The

such that me. given casethe absorption of 1 heat from the Ivolume tube cooled by the engine a I becomes very small or even nil, ;In hot-gas enimportant -that the -mpvable gines it may be heated spaces on; either side piston rings at high temperatures'fbecomes'very "difficult. H v

' Severalconstructions"of movable members reciprocating withou'tfr'ictioharepossible. in one embodiment'ofthe hot 'g'as engine according to 'ftheihvention, theobturationof the space between this movablemember and thewall-of the i r a flexible"elastic material,

: tween thev annular spaces, .at -the,,level ,pi the coolers, is: an annular space. J Lin whicharcooling medium circulates..;, Qonsequently, ,in this embodiment-both the -=working,,spac and the workin space -6 are hot-spaces whereas the workingspaces-Ei and I arecplii spaces.

-. In- Figs 3 ande theJsa-me- -r eierenge; numerals inder wall and to a piston, the-stroke of the pisstons cannot'be large and, consequently, the surface of the piston-like bodies is made large. The working space 4 communicates by way of a channel 20, a heater 2|, a regenerator 22, a cooler 23 and a channel 24 with the working space-5, and the working space 6 communicates by way of a channel 25, a heater 26, a regenerator 21, a cooler 28 anda channel 29 with the working space I. As may be seen from Fig. 4, a sectional area at right angles tothe axis of the working space comprises both heaters for the medium contained in the working spaces 4 and and heaters for the medium contained in the working spaces (i and 1. Here 2| designates the heater elements associated with one cycle and 26 the heater elements associated with the other cycle. It is obvious that the number of elements may be chosenat will, it may, for instance, be desirable to provide thick walls between the various heater elements in which case the annular space may be divided into two parts, one part comprising the heater elements associated with one cycle and the other part comprising the heater elements associated with the other cycle. The pistons may co-operate with a crank-shaft in a manner similar to that shown with reference to the crank-shaft 3 in Fig. 1.

- In Fig. 5, the same reference numerals designate parts corresponding to those of the engine of Figs. land 3. This engine comprises two sets of bellows 30 and 3|, which are adapted to reciprocate with the use of a crank-shaft similar to the crank-shaft 3 shown in Fig. 1. The working space 4 communicates by way of the heater 8, the regenerator 9 and the cooler [0 with the working space 5 and the working space 6 communicates by Way of a heater 32, a regenerator 33 .and a cooler. 34 with the working space 1. The Working spaces 4 and 6 and the working spaces 5 and 1 are similar. Here the working spaces 4 and 6 are hot spaces, and the working spaces 6 and 1 cold spaces.

It will be obvious that the invention may be applied, for example, with an engine in which the centre lines of the members moving with a suitablephase difference are at an angle to one another; Even if these centre lines are parallel to one another, several different constructions may be used successfully. Furthermore, each piston rod may be provided with a plurality of pistons. This provides that more than two cycles can be performed in the engine.

What we claim is:

1. A hotas engine in which two closed thermodynamic cycles are performed comprising a casing formed with two openings therein, a working medium for each cycle, a member in each of said openings acting on the working medium of both cycles and forming workingspaces on each side thereof, said working medium in the working spaces on each side of said member being substantially the same temperature, and ducts bounded by fixed walls connecting the working spaces of each cycle.

2. A hot-gas engine in which two closed thermodynamic cycles are performed comprising a casing formed with a first and second opening 6 therein arranged in tandem, a working medium for each cycle, a member in eachof said openings acting on the working medium in both cycles, said member formingworking spaces on each side thereof in each opening, said working medium in the working spaces on each side of said member being substantially the same temperature, and duct means bounded by fixed walls connecting a space on one side of the mem-- her in said first opening to a space on one side of the member in the second opening and the other space in said first opening to the other space in said second opening.

3. A hot-gas engine in which two closed modynamic cycles are performed comprising a casing formed with a first and second opening therein arranged in tandem, a working medium foreach cycle, a reciprocating member in each of said openings acting on the working medium ofboth cycles, means to reciprocate said members with a phase difference, each of said members forming working spaces on each side thereofin each opening, said Working medium in the working spaces on each side of each of said members being substantially the same temperature, and duct means bounded by fixed walls connecting a space on one side of the member in said first opening to a space on one side of the member in the second opening and the other space in said first opening to the other space in said second opening.

4. A hot-gas engine in which two closed thermodynamic cycles are performed comprisinga casing formed with a first and second opening therein arranged in tandem, a working medium for each cycle, a reciprocating member in each of said openings acting on the working medium of both cycles, a common crankshaft for reciprocating said members, a crank on said crankshaft connecting one member to said crankshaft, a second crank out of phase with said first crank connecting the other member to said crankshaft, said member forming working spaces on each side thereof in each opening, and duct means bounded by fixed walls connecting a space on one side of the member in said first opening to a space on one side of the member in the second openin and the other space in said first opening to the other space in said second opening.

5. A hot-gas engine in which tWo closed thermodynamic cycles are performed comprising a casing formed with a first and second opening therein arranged in tandem, a working medium' for each cycle, a member in each of said openings acting on the working medium in both cycles, said member forming working spaces on each side thereof in each opening, said working medium in the working spaces on each side of said, member bein substantially the same temperature, first and second duct means bounded by fixed walls connecting a space on one side of the member in said first opening to a space on one side of the member in the second opening and the other space in said first opening to the other space in said second opening respectively, both said duct means having herein a heater, a regenerator and a cooler.

6. A hot-gas engine in which two closed thermodynamic cycles are performed comprising a casing formed with a first and second cylindrical opening therein arranged in tandem, a working medium for each cycle, a piston member in each of said cylindrical openings with a small amount of clearance between the piston and the cylinder walls, said piston member acting on the workthers m um in, both was, aid p ston. member;

forming work-ingspaces, en each. si e :t er flf e chf nenin aid workin med m, n th W rk: ing spaces on each side, of, said piston anernber being substantially the same temperature, 11st.

and secondduet meansbounded by fixed. Walls onne ti g a space onone sid of, the memb r in saidfirst openin t sp n ons id 9.

thexmemberxin these ond pen ng-a d th th sp ce in said first openineto the ot e s acc i said second opening respectively, both of said duct .means havingtherein a heater, aregener, ator anda cooler. h

.A :h .t:sas e gine n w ic two c osed therm dynam c cycles, a p rformed com-prisin a GaSiILgiDYmed with first and second cylind ical o e n s h ein arranged in and m, a wor in med um for each cycle, a member in Ba ch ofsaid o en n s aet nsas theworking med um b th said first duct means connectin the other space in saidfirst' opening to the other space in said second opening, both said duct means having therein aheater,;a regenerator and a cooler with thethree latter elements in said first duct means surrounding the corresponding element in said eh ;duct.,me h V r l 8, Ahot-gas engine ,in which two .closed thermodynamic cyclesare performed comprising a casingformed with first and second cylindrical openings therein arranged in tandem, a working medium for each;cycle,a member in each of said openings acting on theworhing medium of both cycles, said n e nbertormin workingspaces on each side thereof in each opening, first duct means bounded by fixed walls connecting a space on oneside of the-member in saidfirst opening toaspage on one side of the member inthe second opening, second duct means connecting the other space saidfirst Opening to the other space in'saidsecond opening, both of said duct means'beingannula and concentric and havingv thereina heatena regeneratorand acooler with the thr'ee latt erlelements in saidfirst duct means suriqounding the corresponding element int-said second;ducti means, an annular space between said iheater elements and an annular space hetween said ,ceoler elements supplied with hot and coldfluidgrespectiyely.

modynaxnic'cycles are performed comprising a casing forn ed with a first and secondcylindricai ient ma erial-elemen sectredto both said m t: er and; h ylind r W 1 and 'i inse osure, filfib Second d c m ans o nd by fi ed 'wan onnectin asn ce onc ideo the emb rsaid iirst open, gyto aspace onone side of the eta cohd p n n nd-the er sna e z n said openin to e o er pacein sa d. econd o ene p ctiv y. oth. of sai du earls ha n the n a he te a --ree e.

, ine in whichmwo closed there moi/hammycles a e-p rme p ising .a asing, term d wi h afi' s a ewh y dr a o ning th r in a ran ed-in nde a ki g medium for each cycle, a movablememberthe formof diaphragm in each of said cylindrical opening ins on the workingmedium in both cyeles member= forming-working spaces oneachdep-thereof in, each opening, a pluralityof duct miiet imsaid du m a being t a l formed; 71, 61- an annular: space provided with partitions; eachof said: duct means having a heater,

a regenerator and; a cooler in said annularspace,

alte n te ductymeans in said annular space connecting corresponding working spaces of each h rmodyn mic l 1.1 Ahotasenei e in w c ,twoclosed t e modynain-iecycles are performed comprising acasing iormed with a first and second opening her n; an ed in tand m; a rkin -med u for -;eaeh=cycle, a movable bellows member in each Q -se d op n s-act o t e o k e medium in both cycles, said member forming Working spaces on each-sidethereoiin each openin first second duct rneansoounded by fixed Wells conne ting-a p t: h id 'th mer s d il t op n n a sp ce o ne s e of t member the, second opening and the 7 pace n sa d fi stpe o the ot e sa d seco d pe n es ect e s d fir n sec nd du m ans ea h h ving t e e n a heater,aregeneratoranda cooler.

.CQRNEXLIQSwQTT-O J ONK-ERS. JAQ'QB .LAURENS :Konlnn. HERRLE RINIA. AUGUST ALBERT LIEBE. References in the file of this patent whe STAT PA N S lfl illlflbal Name 4 Date 228,716 Woodbury et-al June 8, 1880 33%l5 v ,Babc,ocl Jan. 12, 1886 3%,,123 gHopkins Nov. 29, 1887 2,067,453 Lee i i Jan. 12, 193"] 2,272,925 Smith Feb. 10, 1 942 ZASQfiBfi, w-van vw eheh Aug. 30,1949 2,484,392 Van Heeclceren Oct. 11, 194 9 2,564,363 Horowitz .Aus. 1 4, 1951 en, said member a forming working- Spaces on aclgi side thereof, -in each opening, first 

